Loctite® RTV 598™ Black RTV Silicone has a higher temperature rating than 587 Blue RTV (up to 625° F vs 500° F). It also stays flexible and oil resistant longer, which makes it ideal for assemblies that are intended to be permanent. Low odor, non-corrosive formula seals gaps up to 0.25" (6mm). (Not recommended for use on head gaskets or parts immersed in gasoline.) 2.37 oz (70 ml) tube, includes one nozzle.